a parent pulls a sled and rider with a combine weight of 50kg up a 20-meter high hill and then gives the sled a push, providing an initial velocity of 4m/s. Frictional forces acting on the sled do 2000 joules of negative work as the sled moves down the hill. Find the total energy of this system.

Drag each tile to the correct box. tiles bra i sequence

Awind turbine is rotating counterclockwise at 0.5 rev/s and slows to a stop in 10 s. its blades are 20 m in length. (a) what is the angular acceleration of the turbine? (b) what is the centripetal acceleration of the tip of the blades at t=0s? (c) what is the magnitude and direction of the total linear acceleration of the tip of the blades at t=0s?

Large electric fields in cell membranes cause ions to move through the cell wall. the field strength in a typical membrane is 1.0 x 10 7 n/c. what is the magnitude of the force on a calcium ion with charge +e? what is its acceleration? is it possible for a particle with the same charge as as calcium to have a different acceleration if placed at this location? what would change the acceleration: mass of the particle? diameter of the particle?